United States, officially United States of America, abbreviated U.S. or U.S.A., byname America, country in North America, a federal republic of 50 states. Besides the 48 conterminous states that occupy the middle latitudes of the continent, the United States includes the state of Alaska, at the northwestern extreme of North America, and the island state of Hawaii, in the mid-Pacific Ocean. The conterminous states are bounded on the north by Canada, on the east by the Atlantic Ocean, on the south by the Gulf of Mexico and Mexico, and on the west by the Pacific Ocean. The United States is the fourth largest country in the world in area (after Russia, Canada, and China). The national capital is Washington, which is coextensive with the District of Columbia, the federal capital region created in 1790.
The major characteristic of the United States is probably its great variety. Its physical environment ranges from the Arctic to the subtropical, from the moist rain forest to the arid desert, from the rugged mountain peak to the flat prairie. Although the total population of the United States is large by world standards, its overall population density is relatively low. The country embraces some of the world’s largest urban concentrations as well as some of the most extensive areas that are almost devoid of habitation.
The United States does not have an official language, but English is the most commonly spoken language and it is the official language in a number of states. Increasingly, information is also provided in Spanish because of the significant Latino population in the U.S. Besides English, the most commonly spoken languages in the U.S. are Spanish, Chinese, Tagalog, Vietnamese, French, German, Korean, Arabic, Russian and Italian.
Generally, a citizen of a foreign country who wishes to enter the United States must first obtain a visa, either a nonimmigrant visa for temporary stay or an immigrant visa for permanent residence. Citizens of qualified countries may be able to visit the United States without a visa under the Visa Waiver Program. All travelers coming to the United States under the Visa Waiver Program must obtain authorization through the Electronic System for Travel Authorization (ESTA) system prior to initiating travel to the United States.
A visa does not guarantee entry to the United States. A visa simply indicates that a U.S. consular officer has determined that you are eligible to apply for entry to the United States for a specific purpose.
In general, a person who wishes to immigrate to the United States must have a petition approved by the U.S. Citizenship and Immigration Services (USCIS) before applying for an immigrant visa. The petition is filed either by a qualified relative or a potential employer at a USCIS office in the United States. Specific information about filing immigrant petitions is available on the USCIS website. An individual with an approved petition and a priority date that is current for processing (when applicable) is eligible to apply for an immigrant visa or K nonimmigrant visa.
A nonimmigrant visa is used by tourists, business people, students, or specialty workers who wish to stay for a particular period of time in the United States to accomplish specific purposes. According to U.S. visa laws and regulations, most nonimmigrant visa applicants must demonstrate to the consular officer that they have strong ties to their country of residence and must show that they intend to depart the United States after their temporary stay.